Dual-controlled switch



Feb. 10, 1931. R. PENN y DUAL coNTRoLLED swITcH Filed Jan. 28, 1929 Patented Feb. l0, 1931 UNITED STATES PATENT OFFICE RALPH PENN, OF DES MOINES, IOWA, ASSIGNOR TO PENN ELECTRIC SWITCH C0., OF DES MOINES, IOWA, A CORPORATION OF IOWA DUAL-CONTROLLED SWITCH Application iled January 28, 1929. Serial No. 335,652.

The object of my invention is to provide a dual controlled switch of simple, durable and comparatively inexpensive construction.

A further object of my invention is to provide in a switch structure, a safety device for moving the switch to ofi' position, the safety device being operable independent of the normal means of actuating the switch.

More particularly it is my object to provide in connection with a movable member actuated by pressure means to move in opposite directions, a device operated by pressure means from another source of pressure to actuate the movable member upon conditions occurring which might injure the parts of the system in which the device is connected.

Still a further object is to provide in connection with a pressure actuated switch, a safety means for moving the switch to one of its positions independent of the actuating means whereby the system in which the switch is connected may be protected by the safety means. My structure may be used, for instance, in a. refrigerating system. where means controlled by thc temperature of the refrigerant actuates the switch, while the pressure of the refrigerant itself may actuate the safety means. Though temperature conditions call for continued operation of an electric motor, for instance, an abnormal condition Such as clogging of the refrigerant pipes, may operate the safety device to prevent operation of the motor. This prevents continued operation of the motor and at the same time prevents continued operation of the refrigerant compressor until the pipes are cleaned out and thus again put in condition for normal operation of the refrigerating plant.

Another type of installation may call for f the safety device being connected into a certain part of the pressure line with the switch actuating mechanism in another part thereof' so that clogging of the first mentioned part of the pressure line may operate to actuate the switch even though the normal conditions Y callv for a reverse operation of the switch.

With these and other objects in view my invention consists in the construction, ar-

rangement and combination of the various parts of my device, whereby the objects contemplated are attained, as hereinafter more fully set forth, pointed out in myclaims and illustrated in the accompanying drawings. Although the invention is susceptible of a variety of embodiments, it is unnecessary to fully describe and illustrate more than one in order to give a full understanding of the invention both from its structural and functional standpoints. Accordingly, I have illustrated a preferred and desirable embodiment of the invention in the accompanying drawings in which:

Figure 1 is a side elevation of a switch structure to which my safety device, whereby the switch is dual controlled, is applied, parts being broken away and other parts being shown in section and showing the switch in closed position.

Figure 2 is a similar view of a portion of the device showing the switch in open position.

Figure 3 is a sectional view on the line 3-3 of Figure 1; and

Figure 4 is a sectional view on the line 4 4 of Figure 1.

On the accompanying drawings I have used the reference numeral 10 to indicate a switch housing. A switch structure is mounted within the housing 10 and comprises a supporting bar 12, a switch arm 14 carrying contacts 16 and 18 and contacts 20 and 22 supported relative to the bar 12. The switch arm 14 is pivoted to a bracket 24. A bell crank lever consisting of arms 26 and 28 is pivoted at 30 within the casing 10. The arm 28 of the bell crank is connected by a link 32 to the switch arm 14.

Mounted on the switch housing 1() is a bellows housing 34, a bellows 36 is mounted withtype of switch to which my safety device A may be applied for providing a dual control for the switch arm 14. It is obvious that any other type of switch may be used actuated by pressure or otherwise.

My safety device A consists of a bellows housing 50 in which ismounted a bellows 52. The bellows 52 is sealed relative to the housing 50 by a washer 54 and is provided with a head 56. Secured to the head 56is an actue ating pin 58. Opposing the action of the bellows 52 is a spring 60.

Within the switch housing 10 is an arm 62 having ears 64 extending into slots 66 ofthe housing 10. Through the ears 64 is a pivot pin 68 supported in bosses 70. A stop 72 1s provided for the arm 62. A downwardly extending portion 7 4 of the arm 62 is provided with an ear 76 to which is connected one end of a spring 78. Within. the other end of the spring 78 is a plug 80 internally screw threaded to receive an adjusting screw 82.

Pivoted on a pin 84 and supported by a bar 12 is a snap arm 86. The snap arm 86 is operatively connected by means of a link 88 with the ear 76 of the arm 62. l

On the pivot pin 84 a second snap lever 90 is provided. The snap levers 86 and 90 are connected together by means of a spring 92.` The lever 90 is provided with a head 94 preferably of insulation which is adapted to engage the switchL arm 14 as shown in Figure 2 for the purpose'of opening the switch contacts. y i

Swinging movement of the snap lever 90 is limited by means of a 'slot 96 therein and a stop pin 98 mounted in the bar 12.

Practical 'operation In the operation f my device, the bellows housing 84 by means of the connection 100 may be connected with a source of pressure.V

vVariations in the source of pressure will move the arm 26 upwardly or downwardly against the action of the spring 46 and thereby .swing the switch arm 14 for opening and closing the switch contacts 16, 18, 20 and 22.

Thus the device may be connected to a source of pressure for controlling the circuit of a motor, or the like, the operation of which builds up or reduces the pressure depending on the type of installation the device is included in.

' In order that the switch arm 14 may be actuated depending on conditions other than the variations in pressure in the iirst source of pressure, I have provided the safety device described by the reference numerals 5() to 98 inclusive. Under normal operating conditions the parts of the safety device assume the position shown in Figure 1 in which position the head 94 of the arm 90 doesA not affect the switch arm v14. The spring 78 may be adjusted to a predetermined'pressur'e of operation, by way of example, fifty pounds so that 'leave the stop 72 causing the connecting link 88 to move the arm 86 in an anti-clockwise direction. Upon the spring 92 passing the center of the pivot pin 84, the snap lever 90 will snap to the position shown in Figure 2 causingV the head 94 to engage the switch arm and thereby open the switch contacts. The link 32 is connected to the arm 28 by a leaf spring 29 which allows the snap lever 90 to open the switch as shown-in Figure 2.

Thus the safety device normally does n'ot influence the action of the switch 14 but upon excessive pressure being built up within the bellows housing 50, it operates to open the switch.

In the refrigerator installation hereinbefore described, this device serves as a safety so that clogging pipes will stop the operation of the device rather than let it continue to run and probably burst the pipes or otherwise damage the refrigerating system.

My present invention can be used in any installation where it is desirable to provide a safety device operating independent of the normal means for actuating a switch or the like, the safety means actuatingthe switch only upon abnormal conditions occurring.

Some changes may be made in the construction and arrangement of the parts of my device without departing from the real spirit and purpose of my invention and it is my intention to cover by my claims, any modified forms of structure or use of mechanical equivalents, which may be reasonably included within their scope.

I claim as my invention:

1. v.In combination with a movable member and an actuating means therefor, a second actuating means adapted to normally assume a non-operating position, said second actuating means being normally disconnected from said movable member'and operating to move the movable member upon actuation of the second actuatin means, said second actuatingmeans inclu ing a snap acting lever to engage and move the movable member.

2. In a device of the class described, a movable member, actuating means therefor and a safety device normally not affecting the movable member but moving the same upon abnormal conditions occurring, said safety device comprising an actuating means and mechanism movable thereby tov engage the movable member, said mechanism comprising a pair of pivoted arms, one operatively connectcd with the actuating means and the other serving as-an actuator for said movable member and an operative connection between said levers for moving the latter upon actuation of the former with a snap action.

3. In a. device ofthe class described, a movable member, actuating means therefor ,and a. safety device normally not affecting the movable member but moving the same upon abnormal conditions occurring, said safety device comprising an' actuating means and mechanism 'movable thereby to engage the movable member, said mechanism comprising a pair of pivoted arms, one operatively connected with the actuating means and the other serving as an actuator for said movable member and an operative connection between said levers for moving the latter by the former,` said connection including resilient means to cause a snap action of the last men` lioned lever.

4. In a device of the class described, a movable member, actuating means therefor and a safety device normally not affecting the movable member but moving the salne uponabnormal conditions occurring, said safety device comprising an actuating meansand snap acting mechanism movable thereby to engage the movable member, means for imposing a spring tension on the snap acting mechanism and means for adjusting such spring tension whereby the force required for operating the safety device may be varied as desired.

5. In combination with a movable member and an actuating means therefor, a second actuating means and a lever actuated thereby, a second lever connected by a spring to the first lever whereby said second lever normal- 1y assumes a predetermined position but snaps to a new position when the irst lever is moved past apredetermined point due to operation of the second actuating means, said second lever when in its new position being adapted to engage and, move said movable member.l

6. In a device of the class described, a movable member, actuating means therefor and a safety device normally operating within given limits and means including a snap acting lever whereby said movable means is actuated independent of its normal actuating means by operation of the safety device.

7. In a device of the class described, a movable member, actuating means therefor and a safety device normally not affecting the movable member but moving the same upon abnormal conditions occurring, said safety device comprising an actuating means and mechanism movable therebyv to engage the movable member, said mechanism comprising a pair of pivoted arms, one operatively connected with the actuating means and the other serving as an actuator for said movable member.

8. In a device of the class described, a movable member, actuating means therefor and a safety device normally not affecting the mov- 

